An exceptionally preserved specimen of Borealopelta markmitchelli shows the details of this armored dinosaur

Part of Borealopelta markmitchelli fossils (Image courtesy Royal Tyrrell Museum)

An article published in the journal “Current Biology” describes the study of the exceptionally preserved fossils of an armored dinosaur that was named Borealopelta markmitchelli. Classified as part of the nodosaurid (Nodosauridae) family, according to researchers at MIT, Newcastle University, University of Bristol and Royal Tyrrell Museum that examined it despite its armor it was being hunted by predators.

The fossils of the known Borealopelta markmitchelli specimen were discovered in 2011 in an oil sands mine in Alberta, Canada. The Royal Tyrrell Museum was immediately called because it’s a paleontological research center in the area and since the first exam it turned out to be surprising. Initially, they expected to find a marine reptile such as a plesiosaurus because only marine animals were discovered in that type of mine. Instead, it quickly became clear that it was a dinosaur belonging to some species of the ankylosaur (Ankylosauria) genus.

According to the paleontologists, this specimen could have ended up in a flooded river and transported to the sea where it sank. This would explain why it was found in a place out of the ordinary for that type of animal and why the fossilization process was different from the normal one with a more complete preservation of its body.

It took a couple of weeks for the Royal Tyrrell Museum’s staff and the employees of Suncor Energy, the mine’s owner, to extract all that specimen’s fossils and unfortunately there was an accident with the consequence that the piece of rock that contained about half of it broke into pieces.

It took further work to put together the pieces and prevent further damage and the risk that some might get lost. Eventually the fossils were taken to the museum, where they were subjected to a long preparation work and finally in May 2017 they were exhibited, an event that made the news for this specimen’s level of conservation .

Despite the incident, at least some of the fossils retained such a preservation quality that it was compared to a statue. It includes soft tissues, which generally decompose quickly and therefore don’t fossilize. The specimen was about 5,5 meters (18 feet) long for a weight estimated at just over 1,300 kg (3,000 lbs), bigger than today’s terrestrial mammals.

The level of preservation of skin flakes not only shows its appearance but also retains the traces of pigments with their reddish-brown color. This shows that Borealopelta markmitchelli had a form of camouflage of the type where the color is darker on the upper side of the body and lighter on its lower side.

This discovery is part of the surprises experienced during the study of Borealopelta markmitchelli because this animal is much bigger than all those existing today that are have that kind of camouflage. This suggests that this dinosaur, despite its strong armor, was hunted by predators and therefore the evolutionary pressure led to the development of that camouflage.

Taking advantage of the completeness of this specimen, the researchers are still studying it. Modern technologies allow to study a fossil’s interior without destroying it so paleontologists can, for example, examine its digestive tract to try to understand what was this Borealopelta markmitchelli’s last meal. Another study that’s going on concerns its armor’s details.

Since its introduction at the Royal Tyrrell Museum, this Borealopelta markmitchelli made the news thanks to its look determined by its extraordinary level of conservation. It’s a great example of armored dinosaur for the crowd visiting the museum and the potential subject of many studies for paleontologists.